Conceptual and Mathematical Modeling of a Coastal Aquifer in Eastern Delta of R. Nestos (N. Greece)

Abstract

In this paper, the development of the conceptual and groundwater flow model for the coastal aquifer system of the alluvial plain of River Nestos (N. Greece), that suffers from seawater intrusion due to over-pumping for irrigation, is analyzed. The study area is a typical semi-arid hydrogeologic environment, composed of a multi-layer granular aquifers that covers the eastern coastal delta system of R. Nestos. This study demonstrates the results of a series of field measurements (such as geophysical surveys, hydrochemical and isotopical measurements, hydro-meteorological data, land use, irrigation schemes) that were conducted during the period 2009 to 2014. The synthesis of the above resulted in the development of the conceptual model for this aquifer system, that formed the basis for the application of the mathematical model for simulating groundwater flow. The mathematical modeling was achieved using the finite difference method after the application of the USGS code MODFLOW-2005.

Hydrostratigraphic Framework and Physicochemical Status of Groundwater in the Gioia Tauro Coastal Plain (Calabria—Southern Italy)

“…The sustainable development and management of coastal plains have received significant attention worldwide during the last few decades (see, e.g., [1][2][3][4]). However, coastal areas and coastal plains suffer the adverse consequences of geological processes and climate change hazards, including rises in sea level [5].…”

Assessment of Groundwater Vulnerability to Seawater Intrusion Using GALDIT, SITE and SIVI Methods in Laspias River Coastal Aquifer System, NE Greece

“…Evolution of seawater intrusion (E) The study area is mainly covered by clay, sandy clay, sand and, in some cases, pebbles [25]. Nearly all the study area is used for agricultural activities, with the main crops being maize, cereals, cotton and sunflower [24].…”

“…The existence of the seawater intrusion phenomenon in the unconfined aquifer system is demonstrated and confirmed by relevant hydrogeological analyses of the hydrochemical conditions in the study area. Groundwater overpumping is linked to a qualitative degradation of groundwater primarily caused by human activity [25].…”

“…Alternate confined aquifers with a thickness of approximately 200 m make up the second deeper hydrogeological system of the study area. The recharge of the second system comes from lateral groundwater inflows from the nearby hydrogeological basin of Vistonida Lake [25] and Nestos River infiltration through old, buried riverbeds (Figure 1). The groundwater level fluctuations were monitored in the study area during the periods April and October 2023, and piezometric maps of the groundwater system of the study area were designed for the studied aquifer (Figure 4), which is recharged mainly from the N-NE part of the study area and from old riverbeds at the SW part of the study area.…”

“…Alternate confined aquifers with a thickness of approximately 200 m make up the second deeper hydrogeological system of the study area. The recharge of the second system comes from lateral groundwater inflows from the nearby hydrogeological basin of Vistonida Lake [25] and Nestos River infiltration through old, buried riverbeds (Figure 1).…”